2 research outputs found
Device-independent quantum key distribution secure against collective attacks
Device-independent quantum key distribution (DIQKD) represents a relaxation
of the security assumptions made in usual quantum key distribution (QKD). As in
usual QKD, the security of DIQKD follows from the laws of quantum physics, but
contrary to usual QKD, it does not rely on any assumptions about the internal
working of the quantum devices used in the protocol. We present here in detail
the security proof for a DIQKD protocol introduced in [Phys. Rev. Lett. 98,
230501 (2008)]. This proof exploits the full structure of quantum theory (as
opposed to other proofs that exploit the no-signalling principle only), but
only holds again collective attacks, where the eavesdropper is assumed to act
on the quantum systems of the honest parties independently and identically at
each round of the protocol (although she can act coherently on her systems at
any time). The security of any DIQKD protocol necessarily relies on the
violation of a Bell inequality. We discuss the issue of loopholes in Bell
experiments in this context.Comment: 25 pages, 3 figure